相关论文: Photoinduced multistage phase transitions in Ta2Ni…
We combine ultrafast electron diffraction and time-resolved terahertz spectroscopy measurements to unravel the connection between structure and electronic transport properties during the photoinduced insulator-metal transitions in vanadium…
There is growing interest in using ultrafast light pulses to drive functional materials into nonequilibrium states with novel properties. The conventional wisdom is that above gap photoexcitation behaves similarly to raising the electronic…
An emerging area in condensed matter physics is the use of multilayered heterostructures to enhance ferroelectricity in complex oxides. Here, we demonstrate that optically pumping carriers across the interface between thin films of a…
An excitonic insulator phase is expected to arise from the spontaneous formation of electron-hole pairs (excitons) in semiconductors where the exciton binding energy exceeds the size of the electronic band gap. At low temperature, these…
The layered chalcogenide Ta$_{2}$NiSe$_{5}$ has been proposed to host an excitonic condensate in its ground state, a phase that could offer a unique platform to study and manipulate many-body states at room temperature. However, identifying…
Vanadium dioxide (VO2) exhibits an insulator-to-metal transition accompanied by a structural transition near room temperature. This transition can be triggered by an ultrafast laser pulse. Exotic transient states, such as a metallic state…
Ultrafast phase transitions induced by femtosecond light pulses present a new opportunity for manipulating the properties of materials. Understanding how these transient states are different from, or similar to, their thermal counterparts…
Femtosecond time-resolved mid-infrared reflectivity is used to investigate the electron and phonon dynamics occurring at the direct band gap of the excitonic insulator Ta$_2$NiSe$_5$ below the critical temperature of its structural phase…
The temperature dependence of ultrafast photoinduced reflectivity transients is reported in Nd$_{0.5}$Sr$_{0.5}$MnO$_{3}$ thin film. The photoinduced reflectivity shows a complex response with very different temperature dependences on…
We have extended the range of the high-pressure optical spectroscopy to the far-infrared region keeping the accuracy of ambient-pressure experiments. The newly-developed method offers a powerful tool for the study of pressure-induced phase…
In strongly correlated transition metal dichalcogenides, an intricate interplay of polaronic distortions, stacking arrangement, and electronic correlations determines the nature of the insulating state. Here, we study the response of the…
The control of materials properties with light is a promising approach towards the realization of faster and smaller electronic devices. With phases that can be controlled via strain, pressure, chemical composition or dimensionality,…
Nonequilibrium phase transitions driven by light pulses represent a rapidly developing field in condensed matter physics. As one of the archetypal strongly correlated materials, vanadium dioxide (VO2) undergoes a structural phase transition…
Revealing the bonding and time-evolving atomic dynamics in functional materials with complex lattice structures can update the fundamental knowledge on rich physics therein, and also help to manipulate the material properties as desired. As…
Using light to control transient phases in quantum materials is an emerging route to engineer new properties and functionality, with both thermal and non-thermal phases observed out of equilibrium. Transient phases are expected to be…
We report on systematic investigation of hot carrier dynamics in Ti4O7 by ultrafast time-resolved optical reflectivity. We find the transient indication for its two-step insulator-metal (I-M) transition, in which two phase transitions occur…
Intrinsic magnetic topological insulators provide an ideal platform to achieve various exciting physical phenomena. However, this kind of materials and related research are still very rare. In this work, we reported the electronic and…
We report on switching among three charge-density-wave phases - commensurate, nearly commensurate, incommensurate - and the high-temperature normal metallic phase in thin-film 1T-TaS2 devices induced by application of an in-plane electric…
We investigate the non-equilibrium electronic structure and characteristic time scales in a candidate excitonic insulator, Ta$_2$NiSe$_5$, using time- and angle-resolved photoemission spectroscopy with a temporal resolution of 50 fs.…
Ultrafast non-equilibrium dynamics offer a route to study the microscopic interactions that govern macroscopic behavior. In particular, photo-induced phase transitions (PIPTs) in solids provide a test case for how forces, and the resulting…